The invention provides an in-line chromatic harp including a body, a plurality of strings and a string position guide. The body is formed of a pillar, a neck and a sound box. The strings run from the neck to the sound box. The string position guide is movably installed behind the strings, with one end fixed to the pillar and the other end to the neck. This allows a harp player to quickly identify the proper string for each note and to play any chromatic scale as if playing the "C major" scale.